True to form, the reclusive minimalist didn’t show up for his own opening.

“He’s not feeling well,” said host Michael Nevin, publisher of the quarterly arts and culture magazine the journal, adding, “That’s the official story.”

Mr. Lang did materialize a day earlier to set up the exhibit, titled Next Ever After, which consisted of a large disco ball, set on its side in the center of the cracked concrete floor of the journal’s tiny exhibition space on North First Street.

Scratched up, dented and stuck in places with what appeared to be chewed gum, the mounted mirrored ball, which cast spots of light about the small room, wobbled slightly as the swelling crowd of bearded, bespectacled Brooklyners brushed up against it. Some attendees worried it might roll right out the door.

It is possible that the absence of the creator imparted a certain extra sense of artistic mystery and depth to the work. “I don’t even think he exists,” said Jasper Pope, an associate at Chelsea’s Rare Gallery, who was chatting with a friend alongside Mr. Lang’s gleaming object. Mr. Pope works directly beneath the Helmut Lang design studio on West 26th Street. “I think I’ve seen him once,” he said, “though I guess that could have been a look-alike.”

Never much in the public eye, Mr. Lang has all but vanished since he sold his eponymous brand to Prada in 2005.

In an interview with the journal, the designer described his artwork as being about “looking back and moving forward” and “about transitions and new beginnings, representing time as one half respects the past and the other one looks into the future.”

But without the artist on hand to explain it himself, the exhibit was open to interpretation.

“I think someone had an orgy on top of it,” said Mr. Pope, pointing to a peculiar indentation in the disco ball’s northern hemisphere. “I see an ass print.”